What makes you think Buckbeard/The Vandenreich Leader is an Ex-Shinigami? You can't say that for sure.
I don't think he was a Shinigami. We know that there is a complicated conflict between Soul Society and the Quincy and that the Shinigami wiped out nearly all Quincies to prevent Soul Society spilling over in the mortal world which would mean the end of thd world. We've seen how great the animosity between Quincy and Shinigami is/can be when Uryuu was introduced. It'd certainly hurt the pride of a Quincy to bow down to a Shinigami. Also Shinigami don't have the power over Reishi/spirit particles as Quincy have – The Leader manipulated them to construct a stairway to the chamber where Harribel is kept out of the particles from his throne.
"Shinigami use the spiritual power created from their soul in conjunction with their Zanpakutos whereas Quincy use the particles around them" (Source: Bleach-Wiki, Article "Qunicy": [link] )
Given the fact that him and yama duked it out over a thousand years ago and he still didn't age that much (he prob aged a few years or so we can safely deduce that he's a shinigami.
This guy was prob part of squad zero or at least had some connection with the royal society and yes the feud between shinigami and quincies has been going on for more than a thousand years in which the shinigami wiped out almost all of the quincies.
However, as we've clearly seen being a 'quincy' doesn't require you to be human as 'quincy' is a teaching not a race given the fact that even arrancars can become one.
So if say, a shinigami were to learn these teachings then it wouldn't be so far fetched that he'd be able to control and manipulate reishi as he wants.
You've got points there. Giving his age deducing that the Leader is a Shinigami or does at least have some relation to them not illogical. But given the feud between Soul Society and the Quincy I cannot imagine Quincy like Kirge or the blonde guy bow down to a Shinigami as it'd be an offense to the pride of the Quincy.
About teaching Arrancars to use Quincy weapons: That doesn't surprise me after seeing "Quincy: Vollständig" which is like the perfected evolution of "Letzt Stil" where the Quincy can draw out their full power without the drawbacks and the risk of losing one's own power. They managed to achieve that which makes manufacturing Quincy weapons for Arrancars and teaching them how to use those weapons not so difficult. But you have a point there that reishi manipulation doesn't require you to be absolut human.
but who's to say that Kirge was always a quincy...i don't even think he's human.
If Ishida took the blast from Urahara that Kirge did, I don't think he'd been getting up...blut or not blut (or blunt...i can't recall the correct spelling)
That Buckbeard prob found out something he shouldn't (and my guess is that that 'something' was the 'quincy' teaching)...got into a fight with the higher-ups (since it upsets the balance and shit like that) and left SS after his battle with yamamoto.
He prob had some men still loyal to him that went along with him (that pretty-boy quincy being one of them...i think since he's about the only one who can speak to him normally without getting his arm blown off)
I wouldn't be surprised if this guy was the 'first' to become a quincy since his reishi manipulation degree is on a whole other level than any other quincy we've seen.
And about them bowing their heads to a shinigami, who's to say buckbeard even told them he's a shinigami to begin with...it wouldn't make sense raging a war because a shinigami was butthurt at another shinigami so a lie was a necessary must.
At this point I wouldn't be surprised if the king's name would end in "Kurosaki" as Aizen did try to tell Ichigo that he's 'half shinigami and half quincy' but got stopped by Isshin before finishing that sentence.
I don't even think Masaki is his real mother as the hair color simply doesn't match and no matter how you look at it, you just can't get orange hair from black and brown...you just get Isuzu's hair color.
God I can't wait for Kubo to reveal the mystery about his birth and his connection to the Shiba clan.
Buckbeard wouldn't have to tell them if he is a Shinigami or not because as powerful as the Vandenreich members who appeared until now are they should be able to spiritually sense what he is. I think they can tell the difference perfectly without any effort as they're this powerful. So lying would be meaningless.
And about what Aizen told Ichigo that he is half this and half that you're definitely wrong. I've checked that situation on 5 Manga-Sites with at least 3 different versions of translation. In Chapter 397 Aizen tries to tell Ichigo that he's special because he is the son of a Shinigami and something other. In Chapter 398 on each first page Ichigo wonders what Aizen wanted to tell him as he said that Ichigo is a human and something. As Isshin (his real father) shows up, Ichigo realizes that the answer is standing right before his eyes – Isshin Kurosaki, a Shinigami. That makes Ichigo a Human and a Shinigami (different Manga-Sites: [link] ; [link] ; [link] ; [link] ). Don't know where you got that "half Quincy"-stuff and the thing that Buckbeard could be Ichigo's father.
About Masaki: true, the haircolor doesn't really fit, but to me it's Kubo's creative liberty which is responsible for that. Many hair colors in Bleach don't make much sense, but the characters are Kubo's characters so he used different hair colors to accentuate them or something. And that makes it possible for Ichigo to have Masaki as his mother. Also she's a human who maybe could be even spiritually aware. And can you imagine Isshin to be unfaithful to her when we saw him countless times crying in front of a gigantic poster with Masaki's portait on it and even speaking to it? I don't.
So there is no "mystery" about Ichigo's birth. His father is a Shinigami and his mother is a human so that's it what makes him so special. Don't know if Kubo has a parent from Soul Society. And the only connection to the Shiba clan is that Ichigo is said to resemble Kaien Shiba. Also their personalities are quite similar. But the appearance is just coincidence done by Kubo.
-- most important things done --
And what makes you think Kirge is not human? There is no remnant of a mask , so he is no Arrancar. And I don't think that he was a Shinigami before. Maybe Buckbeard could've been one (which I doubt), but most (if not all) of his subordinates should be human.
The abillity is called "Blut", you spelled it right. However, I don't get the point that you bring that up here. There was no part about "Blut" in our discussion.
And about Buckbeard being a Shinigami or not you have your opinion and I have mine. We could discuss until Judgement Day without ever reaching an answer both of us could agree with. So I think it'd be better to stop this here.
We'll just have to wait and see what Kubo has in store for us. He's the only one who knows the truth about Buckbeard and the fight between him and Yamamoto 1000 years ago in the Bleach-storyline.
I'm very curious about the outcome of this, about the Leader's power. Definitely a nice BAMF-Battle foreshadowing.
But there is something about the Vandenreich Leader that keeps bugging me: Yamamoto fought the him 1000 years ago and failed to kill him. How did the Leader live so long till today? We all know that Quincies are like the human opposite of the Shinigami. They are humans who are spiritually aware and can use spirit particles to form weapons, etc. – but aside from that, they are just human. So how could he stay alive so long without aging too much? Don't know if you can explain that with just his spiritual power
With Ivan we seen an Arrancar with Quincy abilities... I'll not be surprised if Buckbeard is a sort of rebel-shinigami. As we don't know a lot of things about the origin of quincy it is a little difficult to understand who is really the leader...
As I mentioned above, I strongly doubt that the Buckbeard/Vandenreich Leader is a Rebel-Shinigami. The Quincy reject the Shinigami and their philosophy that much that it'd definitely be an offense to a Quincy to bow down to a Shinigami. For example, I can't imagine Kirge to be so overly loyal to a Shinigami.
About Arrancar with Qunicy abilities: That shouldn't surprise one when you have seen "Quincy: Vollständig" which is the evolvement/perfection of "Letzt Stil": If they can pull this, then giving Arrancar Qunicy-weapons is a piece of cake. The Qunicy of the Vandenreich could be called Next-Gen-Quincy. But you're right, we definitely don't know much about the origin of Quincy which makes the understanding of the Leader and the Stern Ritter difficult.
If I think that Buckbeard is a shinigami or something else like its, it is only beacause of his longevity. We know only Hollow and Shinigami like species with a very very long life. So for me there aren't a lot of possibility. It will be surprising to see a Quincy be a hollow after all, initially, their work is to kill them. So shinigami is my only idea appropriate for him. The only exception of all of this is Ginjou Kuugo, first half-shinigami but always the physical of a twenty years old guy. Maybe Bucky is also an half-shinigami... Maybe not. Maybe he is a shinigami, maybe not. I have no conviction of what he is you know so when I said "rebel-shinigami" it's only like that, there is not a real reason behind that... ^^'
Maybe Quincy have learned their powers from a shinigami who knows ? Maybe originally Quincy and shinigami are the same. Maybe Quincy abilities is a forgetten branch of kido... One thousand years ago Yamamoto failed to kill (supposely) Buckbeard and Mayuri's words suggest clearly that the Quincy are born at this moment. That can't be a coincidence.
After... I'm not really good in English so it's difficult for me to explain clearly my mind.
I can assure you tthat your English is not bad I get your points (at least I hope so )
You're right about that the Buckbeard/the Leader is definitely not a Hollow. Hollows hunt humans and the job of Quincy is to kill them. Also it'd be quite illogical for a Hollow to maintain a human form in the logic of BLEACH. And thinking about him with taking his longevity as a base the idea of him being a Shinigami is not that far away, I admit that.
Another idea I had about the Leader's longevity is that he could an ability which is similar to the "Blut" ability which allows him to maintain his age.
Your thoughts about that the first Quincy have learned their abilities from Shinigami is not that bad. It's a good question if only humans in the beginning managed to pull that off with just being spiritually aware. If they have been taught about Reishi manipulation then the Shinigami would be definitely more than qualified for the job. But I don't see where Mayuri's words suggested that Yamamoto's mercy over Buckbeard/the Vandenreich Leader is the origin of the Quincy. It'd be the moment where the idea of the Vandenreich was born, but not the whole Quincy organization. I think he and Yamamoto clashed because the feud between Soul Society and the Quincy was already existent 1000 years ago.
But one point is VERY important: The Leader definitely needs to be named!! xD It is a pain in the *** to write "Buckbeard" or "Vandenreich Leader" every single time
"But I don't see where Mayuri's words suggested that Yamamoto's mercy over Buckbeard/the Vandenreich Leader is the origin of the Quincy"
Well... With Kubo Tite's work I have learned that it is better to interpret the word of all the character of Bleach for understand a bit (or a lot) of thing about the story. For me when Mayuri said "the person responsible for what is happening now is no one but you captain commander", the "what is happening now" refers to the arrival of Quincy of today (decleration of war, Sasakibe death, soul society invades, hollow destruction) and just before Mayuri said that "The first time the quincy uryuu ishida infiltrated the seireitei as a ryoka I had already foressen this possibility and warned you about it" and just after he blamed Yamamoto for his choice to not listen him for conclude by his punchline "all what apening now is your fault". In my opinion, when Mayuri said this he said "clearly" that Quincy are appeared or something else like that because Yamamoto doesn't killed Buckbeard. When Mayuri talk I read his explanation like that : Ishida existence is the begining of his argumentation and his conclusion come with Buckbeard existence. In a sense when Mayuri talked he relate the event from the present to the past. And the two are connected and begin with Buckbeard existence. After I see the things like that, that is certainly not true or not completely. The magic of Kubo dialogue... Not enough for have a complete conviction of our ideas =__=
"If they have been taught about Reishi manipulation then the Shinigami would be definitely more than qualified for the job."
But that is why we can think that Quincy and Shinigami have a same origin, that there is no distinction in the past but the "quincy power" began to be forbidden when shinigami seen what the "quincy ability" do. And the time,the "danger" of quincy abilities make coming a discordance into the last generation of shinigami. But the idea I prefer imagine is that Buckbeard invents the quincy's abilities for some troublesome reason (like an Aizen and his magic stone + revolt) and chamber of 46 or even the King don't seen this power with happiness so they decided to kill him. But Buckbeard survived and he began to learn to human the power of using reishi for destroy the hollow. And after we know the story...
And you can name Buckbeard with "Mister mustache" or even "Zangetsu's brother" 4 name for 1 guy... It is original ^^
Of course Yamamoto is responsible for the attack of the Vandenreich as he did not kill Buckbeard when he had the chance to. But that doesn't mean that Buckbeard is THE very first Quincy. He and his ideals are the origin of the Vandenreich and it's members. As Yamamoto did not kill him despite fighting him and his companions (I can't imagine that Buckbeard tried to battle the Gotei 13 on his own without any backup) he gave Buckbeard the chance to begin anew and learn from his and his companion's mistakes to make it better someday which is the current Bleach arc. The Vandenreich-Quincy as we see them were born from the situation between Yamamoto and Buckbeard 1000 years ago, but not the Quincy themselves.
About Shinigami teaching Quincy: They could have the same origin, who knows. Or that the Shinigami thought the first Quincy could help them with their job and taught them to manipulate Reishi because of that reason. Would be a nice plot twist and it makes sense.
But what is true and what is not and wether Buckbeard is a Shinigami or a human is not possible for us to answer clearly at the moment. Kubo is the only one who knows the entire truth. We fans for ourselves could discuss until the end of days without reaching an answer which satisfies everyone. Even Kubo's version won't be able to satisfy every single Bleach-Fan. Let's just hope that he'll get well very soon and continue working on Bleach.